Examples of the prior arts regarding the cryopreservation device include Japanese Unexamined Patent Application, First Publication No. 2005-143873, Japanese Unexamined Patent Application, First Publication No. 2005-156136, and Japanese Unexamined Utility Model Application, First Publication No. Hei 4-15911.
In one of these prior arts, (1) the conformation is adapted, in which a lot of ampoules that include biological samples are stored in a plurality of storing sections of a storing box wherein the storing sections are partitioned, a plurality of these storing boxes are housed in a housing rack, and a plurality of these housing racks that each houses several hundreds to one thousand and several hundreds of ampoules are housed in a cryopreservation vessel that holds a low-temperature liquefied gas such as liquefied nitrogen.
Alternatively, (2) the conformation is adapted, in which a lot of straw tubes that encapsulate biological samples are stored in a plurality of storing sections of a canister wherein the storing sections are partitioned, and a plurality of these canisters that each stores several hundreds of straw tubes are housed in a cryopreservation vessel that holds a low-temperature liquefied gas such as liquefied nitrogen.
The cryopreservation vessels having the aforementioned conformations have the advantage in that it is possible to cryopreserve a lot of, i.e. several thousands of, ampoules and straw tubes that encapsulate cryopreserved samples. However, these cryopreservation vessels have the following disadvantages, and the solution has been desired.
1) In the case of taking out the ampoule or straw tube that encapsulates a target sample, one of the housing rack or canister shall be taken out from the cryopreservation vessel. Therefore, a lot of samples other than the target cryopreserved sample are exposed to an ambient temperature, and the samples suffer damage due to increase in temperature. In addition, the number of times the ampoule or straw tube suffers damage increases.
2) The weight of the one storing rack is several kilograms, and therefore, it becomes difficult to take it into or out of the cryopreservation vessel. Moreover, the housing rack or canister may fall down within the cryopreservation vessel, and the storing box may drop from the housing rack. In addition, the ampoule or straw tube may sink down to the bottom of the cryopreservation vessel so as not to be recovered.
3) It is impossible to detect the preservation position of the housing rack or canister inside from the outside of the cryopreservation vessel. In addition, the sample management is very complicated because a lot of ampoules are stored in the one housing rack or canister.
As one solving the aforementioned problems, the present applicants have already proposed the following cryopreservation vessel as disclosed in Japanese Patent Application No. 2007-130357.
The cryopreservation vessel of the prior invention include, as shown in FIG. 9, a vessel body 1 which holds a low-temperature liquefied gas; a cap 3 which closes an opening section of the vessel body 1 and has a plurality of insertion holes 2 formed to pass through in a vertical direction (a thickness direction); sheath tubes 4 which are inserted into the insertion holes 2 of the cap 3; and ampoule storing tools 5 which are housed so as to be able to pass through the sheath tubes 4, wherein a plurality of gas permeable holes 6 are formed in each of the sheath tubes 4, and the ampoule storing tools 5 are each comprised of a support pillar and a plurality of ampoule storing sections 7 which are attached to the support pillar so as to be arrayed in a vertical direction of the support pillar and stores the ampoules.
In this cryopreservation vessel, the only several ampoules stored in the ampoule storing tool 5 can be taken out from the cryopreservation vessel. Moreover, especially when being stored in the ampoule storing section at the top of the ampoule storing tool, the required ampoule can be taken out without taking the other ampoules out from the cryopreservation vessel, and therefore, it is possible to prevent a lot of samples other than target sample from suffering damage due to increase in temperature.
When the ampoule is stored into or taken out from the cryopreservation vessel, it is unnecessary to remove the cap. Therefore, the evaporation amount of the low-temperature liquefied gas can be reduced.
In addition, the weight of the ampoule storing tools that store a plurality of the ampoules is reduced, and it is possible to reduce the operational burden during taking the ampoule storing tool into or out of the cryopreservation vessel.
Because the sample management can be carried out for each of the ampoules, it is possible to facilitate the complicated sample identification management and to confirm the preservation position of the ampoule from outside of the cryopreservation vessel.
Furthermore, there are the sheath tubes that pass through the cap of the cryopreservation vessel, and therefore, it is possible to prevent the sample loss due to the drop of the ampoule from the ampoule storing tool into the vessel.
Moreover, even when the ampoule drops within the sheath tube, the ampoule is held within the sheath tube, and therefore, the ampoule can be recovered by taking the sheath tube out from the cap.
However, in the cryopreservation vessel of the prior invention, an operator selects the target ampoule storing tool among a lot of ampoule storing tools with visual contact, pulls up it, and takes out the target ampoule among a plurality of ampoules stored in the ampoule storing tool by hand with visual contact.
For this reason, the identification of the ampoule storing tool and ampoule takes long time, and there is a possibility to confuse the ampoule storing tools and ampoules because of human work. Accordingly, there remain points to be improved.    [Patent Document 1]    Japanese Unexamined Patent Application, First Publication No. 2005-143873,    [Patent Document 2]    Japanese Unexamined Patent Application, First Publication No. 2005-156136,    [Patent Document 3]    Japanese Unexamined Utility Model Application, First Publication No. Hei 4-15911.